Finally there is an international effort to combat methane, a greenhouse gas some 23 times more efficient at trapping heat in the atmosphere than CO2. Methane occurs naturally when organic products decay anaerobically (in the absence of oxygen). For years there has been discussion about the amount of methane cows produce, and more recently, the permafrost melting as a result of Global warming has been found to be releasing centuries-old stored methane into the atmosphere. Now the Global Methane Pledge aims to reduce Methane emissions by 30% by 2030 to help limit global warming to the 1.5 degrees agreed in the Paris climate agreement.
How does this affect packaging, you may ask. Methane is one of the many things that upsets the applecart from a sustainable packaging perspective. We would love to be using more renewables that can be grown as crops, or better still crop byproducts, and we certainly should. The difficulty comes when paper-based products either become contaminated with food or recycling bin waste or are laminated with other materials to render them unrecyclable. They will almost inevitably end up in landfill where (you've guessed it) the materials are starved of oxygen and will release methane as they decay.
Ironically this is an argument for waste incineration (sorry, Waste 2 Energy), yet there are potential alternatives. Composting is one, allowing organic waste to decay in the open air, but it can take a very long time for paper-based products to break down.
In-vessel composting makes use of anaerobic digestion in a sealed chamber, with the addition of water and heat to accelerate the process. The methane produced is trapped and collected for use as a fuel. In-vessel composting is typically used to break down food and green waste, yet packaging is barely even considered for composting, teabags being an occasional exception. Card is slower to break down than food or green waste, but the main barrier to inclusion appears to be the non-biodegradable laminations that are so common in food-contact materials.
Bio-based food-contact coatings are available, but not an industry requirement, so don't expect to be putting any paper packaging with your green waste any time soon.
At the moment, there are few options to ensure un recycled bio-based packaging does not release methane at end of life.
Surprisingly packaging already has a useful role to play in reducing methane, by helping fresh food last considerably longer than if it were unpackaged, often by using modified atmosphere packaging (MAP). This means less food goes to waste within the supply chain only to end up in landfill. The downside of MAP is that it tends to rely on fossil plastics to create an effective gas barrier.
It is great that methane is being talked about at last. Let's hope it's not just hot air.
If our thoughts excite you, get in touch with Laurel and Stephen at studio@structuralpackaging.com
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